1. Field of the Invention
The present disclosure relates to an image forming apparatus such as an electrophotographic copying machine, a laser beam printer and the like.
2. Description of the Related Art
An image forming apparatus performs image forming processing by transferring a toner image formed on a photosensitive drum to a recording medium such as a sheet. Toner sometimes remains on the photosensitive drum after the transfer. The toner remaining on the photosensitive drum (hereinafter referred to as “residual toner”) is removed by a cleaner and stored in a collected toner box, provided in the image forming apparatus, as collected toner. The image forming apparatus which forms color images comprises the photosensitive drum for each color. The collected toner box stores the collected toner of each color collected from each of the photosensitive drums. Therefore, the collected toner box needs to have a certain capacity.
When the collected toner box is full of the collected toner, a receiving port of the collected toner is clogged so that the collected toner cannot be collected. In this case, the image forming apparatus prompts a user to replace the collected toner box. The image forming apparatus stops the image forming processing until the collected toner box is replaced.
Japanese Patent Publication No. 4085571 discloses an image forming apparatus which comprises a collected toner box having a plurality of receiving ports of the collected toner. The collected toner is dropped from the receiving port into the collected toner box. A leveling unit is disposed in the collected toner box along the upper limit of the storage space therein. The leveling unit uniformly levels the collected toner stored in the collected toner box to store the collected toner as much as possible.
The image forming apparatus disclosed in Japanese Patent Publication No. 4085571 uniformly levels the collected toner in the collected toner box by the leveling unit at all times. This prevents the collected toner from accumulating in a specific part in the collected toner box. The image forming apparatus, however, causes problems including an occurrence of noise, an increase of consumption power and the like as the leveling unit operates all the time during the image forming processing.